Electronic device with flexible display

ABSTRACT

Provided is an electronic device with high portability, a highly browsable electronic device, or an electronic device having a novel light source that can be used in shooting photographs and video. The electronic device includes a camera and a flexible display portion. The display portion has a first region and a second region. The first region has a function of emitting light to a photographic subject. The second region has a function of displaying an image of the photographic subject shot by the camera. The display portion can be bent so that the first region and the second region face in different directions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/408,642, filed Jan. 18, 2017, now allowed, which is a continuation ofU.S. application Ser. No. 14/616,827, filed Feb. 9, 2015, now U.S. Pat.No. 9,565,366, which claims the benefit of a foreign priorityapplication filed in Japan as Serial No. 2014-024647 on Feb. 12, 2014,all of which are incorporated by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

One embodiment of the present invention relates to a display device, andparticularly to a flexible and bendable display device. Furthermore, oneembodiment of the present invention relates to an electronic deviceincluding a display device.

One embodiment of the present invention is not limited to the abovetechnical field. The technical field of one embodiment of the inventiondisclosed in this specification and the like relates to an object, amethod, or a manufacturing method. One embodiment of the presentinvention relates to a process, a machine, manufacture, or a compositionof matter. Specifically, examples of the technical field of oneembodiment of the present invention disclosed in this specificationinclude a semiconductor device, a display device, a light-emittingdevice, a lighting device, a power storage device, a memory device, amethod for driving any of them, and a method for manufacturing any ofthem.

2. Description of the Related Art

Recent display devices are expected to be applied to a variety of usesand become diversified. For example, display devices for portableelectronic devices and the like are required to be thin, light, androbust. In addition, novel application is required.

Patent Document 1 discloses a flexible active matrix light-emittingdevice in which an organic EL element and a transistor serving as aswitching element are provided over a film substrate.

REFERENCE Patent Document

[Patent Document 1] Japanese Published Patent Application No.2003-174153

SUMMARY OF THE INVENTION

In recent years, browsability of display has been considered to beimproved by enlarging display regions of display devices to display alarger amount of data. However, in applications of portable devices andthe like, an enlargement of display regions might entail a reduction inportability. For this reason, browsability of display and portabilityare difficult to improve at the same time.

Electronic devices such as portable information terminals are desired tomount cameras so that users can shoot photographs and video withoutcircumstance. In addition, light sources for illuminating subjects arerequired to have high luminance with low power consumption.

An object of one embodiment of the present invention is to provide anelectronic device with high portability. Another object is to provide ahighly browsable electronic device. Another object is to provide anelectronic device having a novel light source that can be used inshooting photographs and video. Another object is to provide a noveldisplay device, lighting device, or electronic device.

Note that the descriptions of these objects do not disturb the existenceof other objects. In one embodiment of the present invention, there isno need to achieve all the objects. Other objects will be apparent fromand can be derived from the descriptions of the specification and thelike.

One embodiment of the present invention is an electronic deviceincluding a camera and a flexible display portion. The display portionhas a first region and a second region. The first region has a functionof emitting light to a photographic subject. The second region has afunction of displaying an image of the photographic subject shot by thecamera. The display portion can be bent so that the first region and thesecond region face in different directions.

Another embodiment of the present invention is an electronic deviceincluding a housing, a camera, and a flexible display portion. Thedisplay portion has a region fixed to a first face of the housing. Thecamera has a region fixed to a second face of the housing. The displayportion has a first region and a second region. The first region has afunction of emitting light to a photographic subject. The second regionhas a function of displaying an image of the photographic subject shotby the camera. The display portion can be bent so that the first regionand the second region face in different directions.

It is preferred that the housing have a third face, the third face havea region in contact with the first face, and the display portion have aregion along the third face. The housing preferably has a concaveportion. The display portion can be folded to fit in the concaveportion.

The display portion preferably includes a first pixel and a secondpixel. The first pixel preferably includes a first light-emittingelement. The second pixel preferably includes a second light-emittingelement. A third light-emitting element is preferably provided betweenthe first pixel and the second pixel. It is preferable that the firstpixel and the second pixel each have a function of being controlled byactive matrix driving whereas the third light-emitting element have afunction of being controlled by passive matrix driving.

The display portion preferably includes a third region and a fourthregion. The third region preferably has the first region and the secondregion. The fourth region preferably has a region along an edge of thethird region and preferably includes a fourth light-emitting element.The display portion preferably includes a circuit and a wiring. Thefourth light-emitting element preferably has a region overlapping withone or both of the circuit and the wiring. It is preferable that thethird region have a function of being controlled by active matrixdriving whereas the fourth region have a function of being controlled bypassive matrix driving.

In one embodiment of the present invention, an electronic device withhigh portability, a highly browsable electronic device, or an electronicdevice having a novel light source that can be used in shootingphotographs and video can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1E illustrate an example of an electronic device of anembodiment.

FIGS. 2A and 2B each illustrate an example of an electronic device of anembodiment.

FIGS. 3A and 3B each illustrate an example of an electronic device of anembodiment.

FIGS. 4A to 4D illustrate an example of an electronic device of anembodiment.

FIGS. 5A to 5C illustrate an example of an electronic device of anembodiment.

FIGS. 6A to 6C each illustrate an example of a display portion of anembodiment.

FIGS. 7A to 7C each illustrate an example of an electronic device of anembodiment.

FIGS. 8A to 8D each illustrate an example of a light-emitting panel ofan embodiment.

FIGS. 9A to 9E each illustrate an example of a light-emitting panel ofan embodiment.

FIGS. 10A to 10C illustrate an example of a method for manufacturing alight-emitting panel of an embodiment.

FIGS. 11A to 11C each illustrate an example of a method formanufacturing a light-emitting panel of an embodiment.

FIGS. 12A to 12C illustrate an example of a touch panel of anembodiment.

FIGS. 13A and 13B illustrate an example of a touch panel of anembodiment.

FIGS. 14A to 14C each illustrate an example of a touch panel of anembodiment.

FIGS. 15A to 15C each illustrate an example of a touch panel of anembodiment.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments will be described in detail with reference to theaccompanying drawings. Note that the present invention is not limited tothe description below, and it is easily understood by those skilled inthe art that various changes and modifications can be made withoutdeparting from the spirit and scope of the present invention. Therefore,the present invention should not be construed as being limited to thedescription in the following embodiments.

Note that in the structures of the invention described below, the sameportions or portions having similar functions are denoted by the samereference numerals in different drawings, and description of suchportions is not repeated. The same hatching pattern is applied toportions having similar functions, and the portions are not especiallydenoted by reference numerals in some cases.

Note that in each drawing described in this specification, the size, thelayer thickness, or the region of each component is exaggerated forclarity in some cases. Therefore, the scale is not necessarily limitedto that illustrated in the drawings and the like.

In this specification and the like, ordinal numbers such as “first” and“second” are used in order to avoid confusion among components and donot limit the components numerically.

Embodiment 1

In this embodiment, structure examples of the electronic device of oneembodiment of the present invention will be described.

[Structure Example of Electronic Device]

FIGS. 1A to 1E illustrate an electronic device 100 described below as anexample. FIG. 1A illustrates the electronic device 100 with a displayportion 101 opened. FIGS. 1B and 1C illustrate the electronic device 100with the display portion 101 folded. FIGS. 1D and 1E each illustrate anexample of the electronic device 100 in use.

The electronic device 100 includes the display portion 101 and a housing102.

The display portion 101 is flexible. The display portion 101 is fixed tothe housing 102 at a region in contact with the housing 102. The displayportion 101 includes a display region 103 that displays an image and anon-display region 104 that surrounds the display region 103.

A camera 105 is provided on a face of the housing 102. In FIGS. 1A to1E, the camera 105 is provided on a face of the housing 102 opposite toa face to which the display portion 101 is fixed.

In the electronic device 100 of one embodiment of the present invention,the flexible display portion 101 is partly supported by the housing 102.The display portion 101 can change its form by bending or the like. Forexample, the display portion 101 can be bent so that a display surfacefaces inward (bent inward) or can be bent so that the display surfacefaces outward (bent outward). Note that the display surface of thedisplay portion is a surface on which an image is displayed. The displayportion 101 can also be folded. The electronic device 100 of oneembodiment of the present invention has high portability with thedisplay portion 101 folded, and has high browsability in display withthe display portion 101 opened because the display portion 101 can be aseamless large display region.

The housing 102 has a concave portion. The folded display portion 101can fit in the concave portion. Such a concave portion enables thedisplay portion 101 to prevent or reduce protrusions from the housing102 when folded, which is preferable because the display portion 101 canbe prevented from being damaged in carrying the electronic device 100 ina pocket of clothes or a bag, for example.

To use the electronic device 100 of one embodiment of the presentinvention, the display portion 101 may be opened so that the entiredisplay region 103 can be used as a seamless large display region, orthe display region 103 may be bent so that the display surface of thedisplay portion 101 faces outward and part of the display region 103 canbe used. When the display surface of the display portion 101 is bentinward, part of the display region 103 that is hidden from a user is putin a non-display state, leading to a reduction in power consumption ofthe display portion 101.

The display region 103 of the display portion 101 preferably has apredetermined aspect ratio, e.g., 16:9 in an opened state. In addition,the folded display portion 101 (e.g., in the state illustrated in FIG.1B) preferably has an aspect ratio that is close to that of the openeddisplay portion 101. This means that, the aspect ratio of an image canbe substantially the same in either an opened or a folded state. As aresult, in the case where the same image is displayed on the displayregion 103 in the opened and folded states by zooming in or out, theimage can be displayed on the entire viewed portion of the displayregion 103 almost without leaving an unnatural margin or creating animage distortion caused when the magnification ratios of the width andthe height are different from each other.

The display portion 101 is preferably provided on two or more surfacesof the housing 102. In FIGS. 1A to 1E, the display portion 101 isprovided along one side surface of the housing 102. In such a case, oneimage may be displayed on the entire display region 103 including aportion provided on the side surface of the housing 102. Part of thedisplay region 103 provided on the side surface of the housing 102 candisplay various information, for example, notification of an incomingcall, an e-mail, a social networking service (SNS) massage, or the like;an title or a sender of an e-mail, an SNS massage, or the like; thedate; the time; remaining battery; and the reception strength of anantenna. Alternatively, an image having a function as an operationbutton, an icon, a slider, or the like may be displayed.

FIGS. 1D and 1E illustrate the case of shooting with the camera 105.

Note that part of the display region 103 of the display portion 101 canbe used as a region 111 that functions as a light source for shooting.As illustrated in FIGS. 1D and 1E, part of the display portion 101 isfolded back so as to face in the shooting direction of the camera 105and light is emitted from the region 111, so that a subject can beilluminated brightly.

The region 111 functions as a planar light source and thus produces aneffect of blurring the shading of a subject which is made at the time ofshooting. The shading might be emphasized too much when a point lightsource such as an LED or a flash lamp is used; in contrast, a soft imagecan be shot with the use of light emitted from the region 111.

In addition, power consumption can be extremely low as compared to thecase of using a xenon light source or the like as a light source forilluminating a subject. Accordingly, an extra battery that is necessarywhen a xenon light source or the like is used is not needed. It ispreferable that the size of the region 111 can be freely changed by auser. As the area of the region 111 increases, power consumed to emitlight can be reduced without lowering luminance.

In the case where the region 111 is used as a light source, the entireregion 111 may display the same color, e.g., white. Alternatively, whitewith a color temperature of 2000 K to 8000 K may be displayed, so thatcolor temperatures such as an incandescent color, neutral white, and adaylight color can be displayed. Since the region 111 is part of thedisplay portion 101, light with a variety of colors can be used for alight source. The region 111 may display a single color other thanwhite, such as red, blue, green, or yellow.

Alternatively, the region 111 may be divided into two or more portionsso that different colors can be displayed. Further alternatively, theregion 111 may display colors that gradually change (gradation).

The region 111 may emit light at the timing of shooting or for a certainperiod. It is preferable that light be emitted all the time while videois shot.

As illustrated in FIG. 1E, a region 112 in part that is not folded backof the display region 103 can display a shot image. The shot image ispreferably displayed on the region 112 so as to have a predeterminedaspect ratio, e.g., 4:3. A user can shoot while seeing an imagedisplayed on the region 112. At the same time, the user can adjust thestrength of light emitted from the region 111 and the area of the region111.

A region 113 in the display region 103 can display data on a photographor video. The region 113 may be positioned above, below, on the right,or on the left of the region 112, as long as it is near the region 112.The region 113 may be divided into two or more portions. The region 113may overlap with the region 112. The data that can be displayed on theregion 113 includes the aperture, the shutter speed, the ISOsensitivity, the focal length, setting data of exposure compensation ora filter, the image quality, resolution, size, and number of gray scalesof a shot image, and the selected shooting mode (e.g., a macro mode, anightscape mode, a backlight mode, or an auto mode).

[Other Examples of Electronic Device]

In FIGS. 1A to 1E, the display portion 101 is also provided on the sidesurface of the housing 102; the display portion 101 may also be providedon a face of the housing 102 on which the camera 105 is provided.

FIG. 2A illustrates an example where the display portion 101 is alsoprovided on the back of the housing 102 (the side on which the camera105 is provided). In that case, part of a region of the display portion101, which is provided along the back of the housing 102, is preferablyused as the region 111. In addition to the folded back portion of thedisplay portion 101, the region provided along the back of the housing102 is used as a light source for shooting, whereby the emissionluminance of light can be increased. Moreover, an increase in the areaof the region 111 can enhance the effect of blurring the shading of asubject.

As illustrated in FIG. 2A, the housing 102 may be additionally providedwith a light source 106, e.g., an LED. With such a structure, the lightsources can be used as appropriate depending on the usage.

As illustrated in FIG. 2B, the region of the display portion 101provided along the back of the housing 102 may be provided with anopening portion in a region overlapping with the camera 105. As aresult, the region 111 surrounds the camera 105, in which case a subjectcan be favorably illuminated even when the subject is very close to thecamera 105, for example.

FIGS. 3A and 3B each illustrate a structure in which a light-emittingregion 114 functioning as a light source for shooting is provided inpart of the non-display region 104 that surrounds the display region 103of the display portion 101. The light-emitting region 114 is providedalong an edge of the display region 103.

The light-emitting region 114 may partly or entirely overlap with thenon-display region 104. In the case where part of the display portion101 is also provided on the back of the housing 102 as illustrated inFIG. 3B, the non-display region 104 provided along the back of thehousing 102 may be provided with the light-emitting region 114 partly orentirely.

The light-emitting region 114 includes a light-emitting element. Thelight-emitting element is preferably formed in the same process as alight-emitting element included in the display region 103. Thelight-emitting region 114 preferably overlaps with a circuit for drivinga plurality of pixels included in the display region 103 or a wiringelectrically connected to the plurality of pixels and the circuit.

The light-emitting region 114 preferably includes a plurality oflight-emitting elements that can individually emit light. It is furtherpreferable that each of the light-emitting elements be controlled bypassive matrix driving. Note that one light-emitting element may beprovided over the light-emitting region 114; however, it is preferablethat a plurality of light-emitting elements be provided and their lightemission be individually controlled because light can be emitted onlyfrom a region that faces in the shooting direction of the camera 105.

The plurality of pixels included in the display region 103 and thelight-emitting elements included in the light-emitting region 114 arepreferably controlled by active matrix driving and passive matrixdriving, respectively. With the use of different driving methods in sucha manner, supply of a power supply potential used for driving thelight-emitting region 114 can be interrupted when shooting is notperformed, reducing power consumption. In addition, when shooting isperformed, the display quality of an image (e.g., a shot image)displayed on the display region 103 can be improved. The light-emittingregion 114 is driven when necessary; for example, when the amount oflight emitted from the region 111 is sufficient for shooting, thelight-emitting region 114 is not necessarily driven.

Note that voltage necessary for the light-emitting element in thelight-emitting region 114 to emit light may be different from that for alight-emitting element included in the pixel in the display region 103.When voltage necessary for the light-emitting element in thelight-emitting region 114 to emit light is set higher, for example, theluminance of light emitted from the light-emitting region 114 can behigher than that of light emitted from the region 111. If theselight-emitting elements emit light at the same time, a subject can beirradiated with light with high luminance.

Note that electronic components, for example, a battery, a printedcircuit board on which a variety of ICs such as an arithmetic unit and adriver circuit are mounted, a wireless receiver, a wireless transmitter,a wireless power receiver, and a variety of sensors such as anacceleration sensor are incorporated as appropriate into the housing102, so that the electronic device 100 can function as a portableterminal, a portable image reproducing device, a portable lightingdevice, or the like. A camera, a speaker, a variety of input/outputterminals such as a terminal for power supply, a variety of sensors suchas an optical sensor, an operation button, or the like may also beincorporated into the housing 102.

Note that although the above-described electronic device 100 has onehousing 102, two or more housings may be provided. FIGS. 4A to 4Dillustrate a structure example of an electronic device 150 having threehousings.

FIG. 4A illustrates the electronic device 150 in an opened state. FIG.4B illustrates the electronic device 150 in a folded state. FIG. 4Cillustrates the case where part of the display portion 101 faces in theshooting direction of the camera 105. FIG. 4D is a schematiccross-sectional view taken along line X-Y in FIG. 4A.

The electronic device 150 has three housings (housings 102 a, 102 b, and102 c) that hold the display portion 101. A hinge 151 is providedbetween two housings. The display portion 101 can be bent inward oroutward at the hinge 151.

The electronic components listed above can be incorporated into at leastone of the housings 102 a to 102 c. In that case, the electroniccomponents may be collectively incorporated into one of the housings, ormay be incorporated into a plurality of housings and the electroniccomponents in the housings may be electrically connected to each otherby a wiring or the like which connects the housings through the hinge151. When the electronic components are incorporated into a plurality ofhousings, each housing can be thin.

As illustrated in FIG. 4D, each of the housings preferably includes abattery 152 so that the electronic device 150 can be used for a longtime. When each of the housings is provided with the small battery 152having a predetermined capacity, the physical thickness of each of thebatteries 152 can be reduced, leading to a reduction in the thickness ofthe electronic device 150. A laminated power storage device, e.g., alaminated lithium ion battery, can be used as the battery 152, wherebythe thickness of the battery 152 can be reduced.

In an electronic device 160 illustrated as an example in FIGS. 5A to 5C,the display portion 101 is also provided on side and back surfaces oftwo housings at the ends (the housings 102 a and 102 c). On the back ofthe housing 102 c, the camera 105 is provided at the positionoverlapping with an opening of the display portion 101.

Even in the case where the electronic device 160 includes a plurality ofhousings, the display portion 101 is provided along two or more surfacesof a housing as described above; accordingly, display can be performedon two or more surfaces of the housing even when the electronic device160 is folded.

Although a structure including three housings is described here, thenumber of housings is not limited to three; a structure including twohousings or four or more housings may be used. The camera 105 isprovided on one surface of at least one of a plurality of housings.

Although the thicknesses of the plurality of housings are almost thesame in the above drawings, the thickness of each housing may bedifferent. It is preferable that the thicknesses of two or morehousings, preferably the thicknesses of all the housings be almost thesame, in which case horizontality of a light-emitting surface of theopened electronic device can be maintained easily. Among the pluralityof housings, one incorporating all or most of the above electroniccomponents can be used as a main body having a relatively largethickness, and the other housing(s) can be used as a member having asmaller thickness to simply support the display portion 101.

[Structure Example of Display Portion]

FIG. 6A is a schematic top view of the display portion 101. The displayportion 101 includes, over a flexible substrate 120, the display region103, a circuit 121, a circuit 122, and a plurality of wirings 123. AnFPC 124 electrically connected to the plurality of wirings 123 isattached to the substrate 120. The FPC 124 is provided with an IC 125.

The display region 103 includes a plurality of pixels. Each of thepixels in the display region 103 preferably includes at least onedisplay element. Typical examples of the display element include aliquid crystal element and a light-emitting element such as an organicEL element.

The circuits 121 and 122 each have a function of driving the pixels inthe display region 103. The circuits 121 and 122 each can function as agate driver circuit, for example Although two circuits are provided withthe display region 103 sandwiched therebetween here, the number of thecircuits can be one. In the case where a signal is supplied to thepixels through the FPC 124, the circuits 121 and 122 are not necessary.

The plurality of wirings 123 are electrically connected to the circuit121, the circuit 122, or the pixels in the display region 103.Furthermore, some of the plurality of wirings 123 are electricallyconnected to a terminal that are connected to the FPC 124.

In FIG. 6A, the IC 125 is mounted on the FPC 124 by a COF method or thelike. The IC 125 can function as, for example, a source driver circuit.Alternatively, the IC 125 may have a function of correcting an imagesignal supplied to the display region 103, for example Note that in thecase where a circuit that can function as a source driver circuit isprovided over the flexible substrate 120 or provided outside, the IC 125is not necessary. When the display portion 101 includes a large numberof pixels, a plurality of the FPCs 124 may be provided.

Note that it is preferable that, in the case where the pixels in thedisplay region 103 include light-emitting elements, a potential suppliedto the pixels when the display region 103 displays an image be differentfrom that when the display region 103 functions as a light source forshooting. In that case, current flowing in the light-emitting elementscan be larger when the display region 103 functions as a light sourcefor shooting than when the display region 103 displays an image, leadingto an increase in the luminance of light emitted from the light-emittingelements. When the display region 103 is used as the region 111 thatfunctions as a light source for shooting, for example, a potentialhigher (or lower) than a potential used for displaying an image issupplied to both a wiring serving as a gate line electrically connectedto the pixels and a wiring serving as a signal line.

For this reason, each of the circuits 121 and 122 that can function as agate driver circuit is preferably configured to supply two or morepotentials to the pixels. For example, it is possible that two differentpower lines are provided and a potential of one of the power lines issupplied to the pixels. Furthermore, an output signal is preferably setto be two or more potentials and the IC 125 that can function as asource driver circuit is preferably configured to supply one of thepotentials to the pixels. For example, the IC 125 may include a levelshifter circuit and have a configuration with which an output potential(amplitude) of the level shifter circuit can be changed.

The circuits 121 and 122 may be divided into a plurality of parts andeach part may be driven independently. FIG. 6B illustrates the casewhere the circuit 121 is divided into three parts (circuits 121 a, 121b, and 121 c) and the circuit 122 is divided into three parts (circuits122 a, 122 b, and 122 c). FIG. 6B also illustrates a plurality ofwirings 126 a electrically connected to the circuit 121 a, a pluralityof wirings 126 b electrically connected to the circuit 121 b, aplurality of wirings 127 a electrically connected to the circuit 122 a,and a plurality of wirings 127 b electrically connected to the circuit122 b.

When a circuit that can function as a gate driver circuit is dividedinto a plurality of parts, part of the display region 103 which ishidden when the display portion 101 is folded can be easily controlledso as not to be driven. In addition, supply of a power supply potentialto the circuit can be easily interrupted. As a result, power consumptionof the display portion 101 can be extremely low.

Moreover, when a circuit that can function as a gate driver circuit isdivided into a plurality of parts and each part is driven independently,different potentials can be easily supplied to the display region 103depending on regions. In that case, an image can be easily displayed onthe part of the display region 103 and the other region can be easilyused as the region 111 serving as a light source for shooting. In thestructure illustrated in FIG. 6B, for example, when a power supplypotential supplied to the circuits 121 a and 122 a is higher (or lower)than a power supply potential supplied to the circuits 121 b, 122 b, 121c, and 122 c, the luminance of light emitted from pixels electricallyconnected to the circuits 121 a and 122 a can be higher than that fromthe other pixels.

In FIG. 6C, the light-emitting region 114 that has a function as a lightsource for shooting is provided so as to overlap with the circuits 121and 122 and the plurality of wirings 123. When the light-emitting region114 is provided so as to overlap with the circuits or the wiringspositioned around the display region 103 as described above, the area ofa non-display region of the display portion 101 can be reduced.

[Structure Example of Display Region]

An example where the display region 103 includes a plurality of pixelsfor displaying an image and light-emitting elements between the pixelswill be described below.

FIG. 7A is a schematic top view showing a pattern of pixel electrodes inthe pixels included in the display region 103. Described here is thecase where the display region 103 includes three kinds of pixels of red(R), green (G), and blue (B).

A pixel that emits red light includes a pixel electrode 131R. A pixelthat emits green light includes a pixel electrode 131G A pixel thatemits blue light includes a pixel electrode 131B.

An electrode 132 is provided between adjacent pixels. The electrode 132is arranged in a grid and is electrically isolated from each pixelelectrode.

FIG. 7B is a schematic cross-sectional view of the display portion 101taken along ling A-B in FIG. 7A. FIG. 7B illustrates, as an example, across section of top-emission light-emitting elements to which whiteorganic EL elements are applied and its vicinity. Note that a specificstructure example will be described later.

Each pixel electrode and the electrode 132 are provided over aninsulating layer 141. An insulating layer 143 is provided to cover endportions of each pixel electrode and the electrode 132. Furthermore, alayer containing a light-emitting organic compound (the layer ishereinafter referred to as an EL layer 133) is provided to cover eachpixel electrode, the electrode 132, and the insulating layer 143. Inaddition, an electrode 134 is provided to cover the EL layer 133.

A substrate 142 adhered to the insulating layer 141 with a sealant 144is also provided. Note that color filters 135R, 135G, and 135B areprovided on one surface of the substrate 142. The color filter 135R thattransmits red light is provided so as to overlap with the pixelelectrode 131R. The color filter 135G that transmits green light isprovided so as to overlap with the pixel electrode 131G The color filter135B that transmits blue light is provided so as to overlap with thepixel electrode 131B. A color filter is not provided in a regionoverlapping with the electrode 132.

FIG. 7C illustrates the case of using light-emitting elements formed bya separate coloring method. An EL layer 136R that emits red light, an ELlayer 136G that emits green light, and an EL layer 136B that emits bluelight are provided over the pixel electrode 131R, the pixel electrode131G, and the pixel electrode 131B, respectively. In addition, the ELlayer 133 that emits white light is provided over the electrode 132.

Although a color filter is not provided on the substrate 142 here, colorfilters may be provided in regions overlapping with the pixel electrodesas illustrated in FIG. 7B.

With such structures, the display region 103 can display a full-colorimage. Moreover, white light (W) emitted from the light-emittingelements including the electrode 132, the EL layer 133, and theelectrode 134 can be used for a light source for shooting.

In the case where the display region 103 includes a plurality of theelectrodes 132, light emission from the light-emitting elementsincluding the electrodes can be easily controlled individually. Thelight-emitting elements including the electrode 132 are preferablycontrolled by passive matrix driving, for example, because an additionaltransistor or the like for driving the light-emitting elements is notneeded.

The above is the description of the display region.

Note that an example in which the light-emitting elements are used asdisplay elements is illustrated, one embodiment of the present inventionis not limited to such an example.

In this specification and the like, for example, a display element, adisplay device or a display panel which is a device including a displayelement, a light-emitting element, and a light-emitting device which isa device including a light-emitting element can employ a variety ofmodes or can include a variety of elements. The display element, thedisplay device, the display panel, the light-emitting element, or thelight-emitting device includes at least one of an electroluminescence(EL) element (e.g., an EL element including organic and inorganicmaterials, an organic EL element, or an inorganic EL element), an LED(e.g., a white LED, a red LED, a green LED, or a blue LED), a transistor(a transistor that emits light depending on current), an electronemitter, a liquid crystal element, electronic ink, an electrophoreticelement, a grating light valve (GLV), a plasma display panel (PDP), adisplay element using micro electro mechanical system (MEMS), a digitalmicromirror device (DMD), a digital micro shutter (DMS), MIRASOL(registered trademark), an interferometric modulator display (IMOD)element, a MEMS shutter display element, an optical-interference-typeMEMS display element, an electrowetting element, a piezoelectric ceramicdisplay, a display element including a carbon nanotube, and the like.Other than the above, a display medium whose contrast, luminance,reflectance, transmittance, or the like is changed by electrical ormagnetic action may be included. Note that examples of a display deviceincluding an EL element include an EL display. Examples of a displaydevice including an electron emitter include a field emission display(FED) and an SED-type flat panel display (SED: surface-conductionelectron-emitter display). Examples of a display device including aliquid crystal element include a liquid crystal display (e.g., atransmissive liquid crystal display, a transflective liquid crystaldisplay, a reflective liquid crystal display, a direct-view liquidcrystal display, or a projection liquid crystal display). Examples of adisplay device including electronic ink, Electronic Liquid Powder(registered trademark), or an electrophoretic element include electronicpaper. In the case of a transflective liquid crystal display or areflective liquid crystal display, some or all of pixel electrodesfunction as reflective electrodes. For example, some or all of pixelelectrodes are formed to contain aluminum, silver, or the like. In sucha case, a memory circuit such as an SRAM can be provided under thereflective electrodes, leading to lower power consumption.

For example, in this specification and the like, an active matrix methodin which an active element is included in a pixel or a passive matrixmethod in which an active element is not included in a pixel can beused.

In the active matrix method, as an active element (a non-linearelement), not only a transistor but also various active elements(non-linear elements), for example, a metal insulator metal (MIM), athin film diode (TFD), or the like can be used. Since such an elementhas a small number of manufacturing steps, manufacturing cost can bereduced or yield can be improved. Alternatively, since the size of theelement is small, the aperture ratio can be improved, so that powerconsumption can be reduced or higher luminance can be achieved.

Note that as a method other than an active matrix method, a passivematrix method in which an active element (a non-linear element) is notused can also be used. Since an active element (a non-linear element) isnot used, the number of manufacturing steps is small, so thatmanufacturing cost can be reduced or yield can be improved.Alternatively, since an active element (a non-linear element) is notused, the aperture ratio can be improved, so that power consumption canbe reduced or higher luminance can be achieved, for example.

At least part of this embodiment can be implemented as appropriate incombination with any of the other embodiments described in thisspecification.

Embodiment 2

In this embodiment, structure examples of a light-emitting panel that isapplicable to a display portion included in the electronic device of oneembodiment of the present invention and a method for manufacturing thelight-emitting panel will be described.

Specific Example 1

FIG. 8A is a plan view of a light-emitting panel, and FIG. 8C is anexample of a cross-sectional view taken along dashed-dotted line A1-A2in FIG. 8A. The light-emitting panel described in Specific Example 1 isa top-emission light-emitting panel using a color filter method. In thisembodiment, the light-emitting panel can have, for example, a structurein which sub-pixels of three colors of red (R), green (G), and blue (B)express one color, or a structure in which sub-pixels of four colors ofred (R), green (G), blue (B), and white (W) express one color. There isno particular limitation on a color element, and colors other than R, G,B, and W, for example, yellow, cyan, and magenta, may be used.

The light-emitting panel illustrated in FIG. 8A includes alight-emitting portion 804, driver circuit portions 806, and a flexibleprinted circuit (FPC) 808. Light-emitting elements and transistorsincluded in the light-emitting portion 804 and the driver circuitportions 806 are sealed by a substrate 801, a substrate 803, and asealing layer 823.

The light-emitting panel illustrated in FIG. 8C includes the substrate801, an adhesive layer 811, an insulating layer 813, a plurality oftransistors, a conductive layer 857, an insulating layer 815, aninsulating layer 817, a plurality of light-emitting elements, aninsulating layer 821, the sealing layer 823, an overcoat 849, a coloringlayer 845, a light-blocking layer 847, an insulating layer 843, anadhesive layer 841, and the substrate 803. The sealing layer 823, theovercoat 849, the insulating layer 843, the adhesive layer 841, and thesubstrate 803 transmit visible light.

The light-emitting portion 804 includes a transistor 820 and alight-emitting element 830 over the substrate 801 with the adhesivelayer 811 and the insulating layer 813 provided between the substrate801 and each of the transistor 820 and the light-emitting element 830.The light-emitting element 830 includes a lower electrode 831 over theinsulating layer 817, an EL layer 833 over the lower electrode 831, andan upper electrode 835 over the EL layer 833. The lower electrode 831 iselectrically connected to a source electrode or a drain electrode of thetransistor 820. An end portion of the lower electrode 831 is coveredwith the insulating layer 821. The lower electrode 831 preferablyreflects visible light. The upper electrode 835 transmits visible light.

The light-emitting portion 804 also includes the coloring layer 845overlapping with the light-emitting element 830 and the light-blockinglayer 847 overlapping with the insulating layer 821. The coloring layer845 and the light-blocking layer 847 are covered with the overcoat 849.The space between the light-emitting element 830 and the overcoat 849 isfilled with the sealing layer 823.

The insulating layer 815 has an effect of suppressing diffusion ofimpurities into a semiconductor included in the transistor. As theinsulating layer 817, an insulating layer having a planarizationfunction is preferably selected in order to reduce surface unevennessdue to the transistor.

The driver circuit portion 806 each include a plurality of transistorsover the substrate 801 with the adhesive layer 811 and the insulatinglayer 813 provided between the substrate 801 and the transistors. FIG.8C illustrates one of the transistors included in one of the drivercircuit portions 806.

The insulating layer 813 and the substrate 801 are attached to eachother with the adhesive layer 811. The insulating layer 843 and thesubstrate 803 are attached to each other with the adhesive layer 841. Itis preferable to use films with low water permeability for theinsulating layers 813 and 843, in which case an impurity such as watercan be prevented from entering the light-emitting element 830 or thetransistor 820, leading to improved reliability of the light-emittingpanel.

The conductive layer 857 is electrically connected to an external inputterminal through which a signal (e.g., a video signal, a clock signal, astart signal, and a reset signal) or a potential from the outside istransmitted to the driver circuit portion 806. Here, an example in whichthe FPC 808 is provided as the external input terminal is described. Toprevent an increase in the number of fabrication steps, the conductivelayer 857 is preferably formed using the same material and step as theelectrode or the wiring in the light-emitting portion or the drivercircuit portion. Here, an example in which the conductive layer 857 isformed using the same material and step as the electrodes included inthe transistor 820 is described.

In the light-emitting panel illustrated in FIG. 8C, a connector 825 ispositioned over the substrate 803. The connector 825 is connected to theconductive layer 857 through an opening provided in the substrate 803,the adhesive layer 841, the insulating layer 843, the sealing layer 823,the insulating layer 817, and the insulating layer 815. The connector825 is also connected to the FPC 808. The FPC 808 and the conductivelayer 857 are electrically connected to each other via the connector825. In the case where the conductive layer 857 overlaps with thesubstrate 803, the conductive layer 857, the connector 825, and the FPC808 can be electrically connected to one another by forming an openingin the substrate 803 (or using a substrate having an opening portion).

The light-emitting panel in Specific Example 1 can be manufactured inthe following manner: the insulating layer 813, the transistor 820, andthe light-emitting element 830 are formed over a formation substratewith high heat resistance; the formation substrate is separated; and theinsulating layer 813, the transistor 820, and the light-emitting element830 are transferred to the substrate 801 and attached thereto with theadhesive layer 811. The light-emitting panel in Specific Example 1 canbe manufactured in the following manner: the insulating layer 843, thecoloring layer 845, and the light-blocking layer 847 are formed over aformation substrate with high heat resistance; the formation substrateis separated; and the insulating layer 843, the coloring layer 845, andthe light-blocking layer 847 are transferred to the substrate 803 andattached thereto with the adhesive layer 841.

In the case where a material with low heat resistance (e.g., resin) isused for a substrate, it is difficult to expose the substrate to hightemperatures in the manufacturing process. Thus, there is a limitationon conditions for forming a transistor and an insulating layer over thesubstrate. In the case of using a material with high water permeability(e.g., a resin), it is preferable to form a film at high temperatures tohave low water permeability. In the manufacturing method of thisembodiment, a transistor and the like can be formed over a formationsubstrate with high heat resistance; thus, a highly reliable transistorand a film with sufficiently low water permeability can be formed athigh temperatures. Then, the transistor and the film are transferred tothe substrate 801 and the substrate 803, whereby a highly reliablelight-emitting panel can be manufactured. Thus, according to oneembodiment of the present invention, a thin and/or lightweight andhighly reliable light-emitting panel can be provided. Details of themanufacturing method will be described later.

Specific Example 2

FIG. 8B is a plan view of a light-emitting panel, and FIG. 8D is anexample of a cross-sectional view taken along dashed-dotted line A3-A4in FIG. 8B. The light-emitting panel described in Specific Example 2 isa top-emission light-emitting panel using a color filter method, whichis different from that described in Specific Example 1. Portionsdifferent from those in Specific Example 1 will be described in detailhere and the descriptions of portions common to those in SpecificExample 1 will be omitted.

The light-emitting panel illustrated in FIG. 8D is different from thelight-emitting panel illustrated in FIG. 8C in the aspects below.

The light-emitting panel illustrated in FIG. 8D includes a spacer 827over the insulating layer 821. The spacer 827 can adjust the distancebetween the substrate 801 and the substrate 803.

In the light-emitting panel illustrated in FIG. 8D, the substrate 801and the substrate 803 have different sizes. The connector 825 ispositioned over the insulating layer 843 and thus does not overlap withthe substrate 803. The connector 825 is connected to the conductivelayer 857 through an opening provided in the insulating layer 843, thesealing layer 823, the insulating layer 817, and the insulating layer815. Since no opening needs to be provided in the substrate 803, thereis no limitation on the material of the substrate 803.

Specific Example 3

FIG. 9A is a plan view of a light-emitting panel, and FIG. 9C is anexample of a cross-sectional view taken along dashed-dotted line A5-A6in FIG. 9A. The light-emitting panel described in Specific Example 3 isa top-emission light-emitting panel using a separate coloring method.

The light-emitting panel illustrated in FIG. 9A includes thelight-emitting portion 804, the driver circuit portion 806, and the FPC808. Light-emitting elements and transistors included in thelight-emitting portion 804 and the driver circuit portion 806 are sealedby the substrate 801, the substrate 803, a frame-like sealing layer 824,and the sealing layer 823.

The light-emitting panel illustrated in FIG. 9C includes the substrate801, the adhesive layer 811, the insulating layer 813, a plurality oftransistors, the conductive layer 857, the insulating layer 815, theinsulating layer 817, a plurality of light-emitting elements, theinsulating layer 821, the sealing layer 823, the frame-like sealinglayer 824, and the substrate 803. The sealing layer 823 and thesubstrate 803 transmit visible light.

The frame-like sealing layer 824 preferably has a higher gas barrierproperty than the sealing layer 823 to prevent entry of moisture andoxygen from the outside into the light-emitting panel. Thus, thelight-emitting panel can be highly reliable.

In Specific Example 3, light emitted from the light-emitting element 830in the light-emitting panel is extracted through the sealing layer 823.For this reason, the sealing layer 823 preferably has a higherlight-transmitting property and a higher refractive index than theframe-like sealing layer 824. In addition, it is preferable that areduction in the volume of the sealing layer 823 by curing be smallerthan that of the frame-like sealing layer 824.

The light-emitting portion 804 includes the transistor 820 and thelight-emitting element 830 over the substrate 801 with the adhesivelayer 811 and the insulating layer 813 provided between the substrate801 and each of the transistor 820 and the light-emitting element 830.The light-emitting element 830 includes the lower electrode 831 over theinsulating layer 817, the EL layer 833 over the lower electrode 831, andthe upper electrode 835 over the EL layer 833. The lower electrode 831is electrically connected to the source electrode or the drain electrodeof the transistor 820. The end portion of the lower electrode 831 iscovered with the insulating layer 821. The lower electrode 831preferably reflects visible light. The upper electrode 835 transmitsvisible light.

The driver circuit portion 806 includes a plurality of transistors overthe substrate 801 with the adhesive layer 811 and the insulating layer813 provided between the substrate 801 and the transistors. FIG. 9Cillustrates one of the transistors included in the driver circuitportion 806.

The insulating layer 813 and the substrate 801 are attached to eachother with the adhesive layer 811. It is preferable to use a film withlow water permeability for the insulating layer 813, in which case animpurity such as water can be prevented from entering the light-emittingelement 830 or the transistor 820, leading to improved reliability ofthe light-emitting panel.

The conductive layer 857 is electrically connected to an external inputterminal through which a signal or a potential from the outside istransmitted to the driver circuit portion 806. Here, an example in whichthe FPC 808 is provided as the external input terminal is described.Moreover, here, an example in which the conductive layer 857 is formedusing the same material and step as the electrodes included in thetransistor 820 is described.

In the light-emitting panel illustrated in FIG. 9C, the connector 825 ispositioned over the substrate 803. The connector 825 is connected to theconductive layer 857 through an opening provided in the substrate 803,the sealing layer 823, the insulating layer 817, and the insulatinglayer 815. The connector 825 is also connected to the FPC 808. The FPC808 and the conductive layer 857 are electrically connected to eachother via the connector 825.

The light-emitting panel in Specific Example 3 can be manufactured inthe following manner: the insulating layer 813, the transistor 820, andthe light-emitting element 830 are formed over a formation substratewith high heat resistance; the formation substrate is separated; and theinsulating layer 813, the transistor 820, and the light-emitting element830 are transferred to the substrate 801 and attached thereto with theadhesive layer 811. A transistor and the like can be formed over aformation substrate with high heat resistance; thus, a highly reliabletransistor and a film with sufficiently low water permeability can beformed at high temperatures. Then, the transistor and the film aretransferred to the substrate 801, whereby a highly reliablelight-emitting panel can be manufactured. Thus, according to oneembodiment of the present invention, a thin and/or lightweight andhighly reliable light-emitting panel can be provided.

Specific Example 4

FIG. 9B is a plan view of a light-emitting panel, and FIG. 8D is anexample of a cross-sectional view taken along dashed-dotted line A7-A8in FIG. 9B. The light-emitting panel described in Specific Example 4 isa bottom-emission light-emitting panel using a color filter method.

The light-emitting panel illustrated in FIG. 9D includes the substrate801, the adhesive layer 811, the insulating layer 813, a plurality oftransistors, the conductive layer 857, the insulating layer 815, thecoloring layer 845, an insulating layer 817 a, an insulating layer 817b, a conductive layer 816, a plurality of light-emitting elements, theinsulating layer 821, the sealing layer 823, and the substrate 803. Thesubstrate 801, the adhesive layer 811, the insulating layer 813, theinsulating layer 815, the insulating layer 817 a, and the insulatinglayer 817 b transmit visible light.

The light-emitting portion 804 includes the transistor 820, a transistor822, and the light-emitting element 830 over the substrate 801 with theadhesive layer 811 and the insulating layer 813 provided between thesubstrate 801 and each of the transistor 820, the transistor 822, andthe light-emitting element 830. The light-emitting element 830 includesthe lower electrode 831 over the insulating layer 817, the EL layer 833over the lower electrode 831, and the upper electrode 835 over the ELlayer 833. The lower electrode 831 is electrically connected to thesource electrode or the drain electrode of the transistor 820. The endportion of the lower electrode 831 is covered with the insulating layer821. The upper electrode 835 preferably reflects visible light. Thelower electrode 831 transmits visible light. The coloring layer 845 thatoverlaps with the light-emitting element 830 can be provided anywhere;for example, the coloring layer 845 may be provided between theinsulating layers 817 a and 817 b or between the insulating layers 815and 817 a.

The driver circuit portion 806 includes a plurality of transistors overthe substrate 801 with the adhesive layer 811 and the insulating layer813 provided between the substrate 801 and the transistors. FIG. 9Dillustrates two of the transistors included in the driver circuitportion 806.

The insulating layer 813 and the substrate 801 are attached to eachother with the adhesive layer 811. It is preferable to use a film withlow water permeability for the insulating layer 813, in which case animpurity such as water can be prevented from entering the light-emittingelement 830, the transistor 820, or the transistor 822, leading toimproved reliability of the light-emitting panel.

The conductive layer 857 is electrically connected to an external inputterminal through which a signal or a potential from the outside istransmitted to the driver circuit portion 806. Here, an example in whichthe FPC 808 is provided as the external input terminal is described.Moreover, here, an example in which the conductive layer 857 is formedusing the same material and step as the conductive layer 816 isdescribed.

The light-emitting panel in Specific Example 4 can be manufactured inthe following manner: the insulating layer 813, the transistor 820, thelight-emitting element 830, and the like are formed over a formationsubstrate with high heat resistance; the formation substrate isseparated; and the insulating layer 813, the transistor 820, thelight-emitting element 830, and the like are transferred to thesubstrate 801 and attached thereto with the adhesive layer 811. Atransistor and the like can be formed over a formation substrate withhigh heat resistance; thus, a highly reliable transistor and a film withsufficiently low water permeability can be formed at high temperatures.Then, the transistor and the film are transferred to the substrate 801,whereby a highly reliable light-emitting panel can be manufactured.Thus, according to one embodiment of the present invention, a thinand/or lightweight and highly reliable light-emitting panel can beprovided.

Specific Example 5

FIG. 9E illustrates an example of a light-emitting panel that isdifferent from those described in Specific Examples 1 to 4.

The light-emitting panel illustrated in FIG. 9E includes the substrate801, the adhesive layer 811, the insulating layer 813, a conductivelayer 814, a conductive layer 857 a, a conductive layer 857 b, thelight-emitting element 830, the insulating layer 821, the sealing layer823, and the substrate 803.

The conductive layer 857 a and the conductive layer 857 b, which areexternal connection electrodes of the light-emitting panel, can each beelectrically connected to an FPC or the like.

The light-emitting element 830 includes the lower electrode 831, the ELlayer 833, and the upper electrode 835. The end portion of the lowerelectrode 831 is covered with the insulating layer 821. Thelight-emitting element 830 is a bottom-emission, top-emission, ordual-emission light-emitting element. An electrode, a substrate, aninsulating layer, and the like on the light extraction side transmitvisible light. The conductive layer 814 is electrically connected to thelower electrode 831.

The substrate through which light is extracted may have, as a lightextraction structure, a hemispherical lens, a micro lens array, a filmprovided with an uneven surface structure, a light diffusing film, orthe like. For example, the substrate with a light extraction structurecan be formed by attaching the above lens or film to a resin substratewith an adhesive or the like having substantially the same refractiveindex as the substrate, or the lens or film.

The conductive layer 814 is preferably, though not necessarily, providedbecause voltage drop due to the resistance of the lower electrode 831can be prevented. In addition, for a similar purpose, a conductive layerelectrically connected to the upper electrode 835 may be provided overthe insulating layer 821, the EL layer 833, the upper electrode 835, orthe like.

The conductive layer 814 can be a single layer or a stacked layer formedusing a material selected from copper, titanium, tantalum, tungsten,molybdenum, chromium, neodymium, scandium, nickel, or aluminum; an alloymaterial containing any of these materials as its main component; or thelike. The thickness of the conductive layer 814 can be, for example,greater than or equal to 0.1 μm and less than or equal to 3 μm,preferably greater than or equal to 0.1 μm and less than or equal to 0.5μm.

When a paste (e.g., silver paste) is used as a material for theconductive layer electrically connected to the upper electrode 835,metal particles forming the conductive layer aggregate; therefore, thesurface of the conductive layer is rough and has many gaps. Thus, it isdifficult for the EL layer 833 to completely cover the conductive layer;accordingly, the upper electrode and the conductive layer are preferablyelectrically connected to each other easily.

The light-emitting panel in Specific Example 5 can be manufactured inthe following manner: the insulating layer 813, the light-emittingelement 830, and the like are formed over a formation substrate withhigh heat resistance; the formation substrate is separated; and theinsulating layer 813, the light-emitting element 830, and the like aretransferred to the substrate 801 and attached thereto with the adhesivelayer 811. The insulating layer 813 and the like with sufficiently lowwater permeability are formed over the formation substrate with highheat resistance at high temperatures and then are transferred to thesubstrate 801, whereby a highly reliable light-emitting panel can bemanufactured. Thus, according to one embodiment of the presentinvention, a thin and/or lightweight and highly reliable light-emittingpanel can be provided.

<Examples of Materials>

Next, materials and the like that can be used for a light-emitting panelare described. Note that description on the components already describedin this specification is omitted in some cases.

For each of the substrates, a material such as glass, quartz, an organicresin, a metal, or an alloy can be used. For the substrate on the sidefrom which light from the light-emitting element is extracted, amaterial which transmits that light is used.

It is particularly preferable to use a flexible substrate. For example,an organic resin; a glass material, a metal, or an alloy that is thinenough to have flexibility; or the like can be used.

An organic resin, which has a specific gravity smaller than that ofglass, is preferably used for the flexible substrate, in which case thelight-emitting panel can be more lightweight than in the case whereglass is used.

The substrates are preferred to be formed using a material with hightoughness. In that case, a light-emitting panel with high impactresistance that is robust can be provided. For example, when an organicresin substrate, a thin metal substrate, or a thin alloy substrate isused, the light-emitting panel can be lighter and more robust than thecase where a glass substrate is used.

A metal material and an alloy material, which have high thermalconductivity, are preferred because they can easily conduct heat to thewhole substrate and accordingly can prevent a local temperature rise inthe light-emitting panel. The thickness of a substrate using a metalmaterial or an alloy material is preferably greater than or equal to 10μm and less than or equal to 200 μm, further preferably greater than orequal to 20 μm and less than or equal to 50 μm.

There is no particular limitation on a material of the metal substrateor the alloy substrate, but it is preferable to use, for example,aluminum, copper, nickel, a metal alloy such as an aluminum alloy orstainless steel.

Furthermore, when a material with high thermal emissivity is used forthe substrate, the surface temperature of the light-emitting panel canbe prevented from rising, leading to prevention of breakage or adecrease in reliability of the light-emitting panel. For example, thesubstrate may have a stacked-layer structure of a metal substrate and alayer with high thermal emissivity (e.g., the layer can be formed usinga metal oxide or a ceramic material).

Examples of such a material having flexibility and a light-transmittingproperty include polyester resins such as polyethylene terephthalate(PET) and polyethylene naphthalate (PEN), a polyacrylonitrile resin, apolyimide resin, a polymethyl methacrylate resin, a polycarbonate (PC)resin, a polyethersulfone (PES) resin, a polyamide resin, a cycloolefinresin, a polystyrene resin, a polyamide imide resin, and a polyvinylchloride resin. In particular, a material whose coefficient of thermalexpansion is low is preferred, and for example, a polyamide imide resin,a polyimide resin, or PET can be suitably used. A substrate in which afibrous body is impregnated with a resin (also referred to as prepreg)or a substrate whose coefficient of thermal expansion is reduced bymixing an organic resin with an inorganic filler can also be used.

The flexible substrate may have a stacked-layer structure in which ahard coat layer (such as a silicon nitride layer) by which a surface ofa light-emitting device is protected from damage, a layer (such as anaramid resin layer) that can disperse pressure, or the like is stackedover a layer of any of the above-mentioned materials.

The flexible substrate may be formed by stacking a plurality of layers.When a glass layer is used, a barrier property against water and oxygencan be improved and thus a reliable light-emitting panel can beprovided.

For example, a flexible substrate in which a glass layer, an adhesivelayer, and an organic resin layer are stacked from the side closer to alight-emitting element can be used. The thickness of the glass layer isgreater than or equal to 20 μm and less than or equal to 200 μm,preferably greater than or equal to 25 μm and less than or equal to 100μm. With such a thickness, the glass layer can have both an excellentbarrier property against water and oxygen and a high flexibility. Thethickness of the organic resin layer is greater than or equal to 10 μmand less than or equal to 200 μm, preferably greater than or equal to 20μm and less than or equal to 50 μm. Providing such organic resin layeroutside the glass layer, occurrence of a crack or a break in the glasslayer can be suppressed and mechanical strength can be improved. Withthe substrate that includes such a composite material of a glassmaterial and an organic resin, a highly reliable and flexiblelight-emitting panel can be provided.

As the adhesive layer or the sealing layer, a variety of curableadhesives such as a reactive curable adhesive, a thermosetting adhesive,an anaerobic adhesive, and a photo curable adhesive such as anultraviolet curable adhesive can be used. Examples of these adhesivesinclude an epoxy resin, an acrylic resin, a silicone resin, a phenolresin, a polyimide resin, an imide resin, a polyvinyl chloride (PVC)resin, a polyvinyl butyral (PVB) resin, and an ethylene vinyl acetate(EVA) resin. A material with low moisture permeability, such as an epoxyresin, is particularly preferable. Alternatively, atwo-component-mixture-type resin may be used. Alternatively, an adhesivesheet or the like may be used.

The resin may include a drying agent. As the drying agent, for example,a substance that adsorbs moisture by chemical adsorption, such as anoxide of an alkaline earth metal (e.g., calcium oxide or barium oxide),can be used. Alternatively, a substance that adsorbs moisture byphysical adsorption, such as zeolite or silica gel, may be used. Thedrying agent is preferably included because it can prevent an impuritysuch as moisture from entering the functional element, thereby improvingthe reliability of the light-emitting panel.

In addition, it is preferable to mix a filler with a high refractiveindex or light-scattering member into the resin, in which case theefficiency of light extraction from the light-emitting element can beimproved. For example, titanium oxide, barium oxide, zeolite, zirconium,or the like can be used.

There is no particular limitation on the structure of the transistors inthe light-emitting panel. For example, a forward staggered transistor oran inverted staggered transistor may be used. A top-gate transistor or abottom-gate transistor may be used. There is no particular limitation ona semiconductor material used for the transistors; for example, siliconor germanium can be used. Alternatively, an oxide semiconductorcontaining at least one of indium, gallium, and zinc, such as anIn—Ga—Zn-based metal oxide, may be used.

There is no particular limitation on the crystallinity of asemiconductor material used for the transistors, and an amorphoussemiconductor or a semiconductor having crystallinity (amicrocrystalline semiconductor, a polycrystalline semiconductor, asingle-crystal semiconductor, or a semiconductor partly includingcrystal regions) may be used. It is preferable that a semiconductorhaving crystallinity be used, in which case deterioration of thetransistor characteristics can be suppressed.

For stable characteristics of the transistor, a base film is preferablyprovided. The base film can be formed with an inorganic insulating filmsuch as a silicon oxide film, a silicon nitride film, a siliconoxynitride film, or a silicon nitride oxide film to have a single-layerstructure or a stacked-layer structure. The base film can be formed by asputtering method, a chemical vapor deposition (CVD) method (e.g., aplasma CVD method, a thermal CVD method, or a metal organic CVD (MOCVD)method), an atomic layer deposition (ALD) method, a coating method, aprinting method, or the like. Note that the base film is not necessarilyprovided. In each of the above Structure Examples, the insulating layer813 can serve as a base film of the transistor.

As the light-emitting element, a self-luminous element can be used, andan element whose luminance is controlled by current or voltage isincluded in the category of the light-emitting element. For example, alight-emitting diode (LED), an organic EL element, an inorganic ELelement, or the like can be used.

The light-emitting element may be a top emission, bottom emission, ordual emission light-emitting element. A conductive film that transmitsvisible light is used as the electrode through which light is extracted.A conductive film that reflects visible light is preferably used as theelectrode through which light is not extracted.

The conductive film that transmits visible light can be formed using,for example, indium oxide, indium tin oxide (ITO), indium zinc oxide,zinc oxide, or zinc oxide to which gallium is added. Alternatively, afilm of a metal material such as gold, silver, platinum, magnesium,nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium,or titanium; an alloy containing any of these metal materials; or anitride of any of these metal materials (e.g., titanium nitride) can beformed thin so as to have a light-transmitting property. Alternatively,a stack of any of the above materials can be used as the conductivelayer. For example, a stacked film of ITO and an alloy of silver andmagnesium is preferably used, in which case conductivity can beincreased. Further alternatively, graphene or the like may be used.

For the conductive film that reflects visible light, for example, ametal material such as aluminum, gold, platinum, silver, nickel,tungsten, chromium, molybdenum, iron, cobalt, copper, or palladium or analloy containing any of these metal materials can be used. Lanthanum,neodymium, germanium, or the like may be added to the metal material orthe alloy. Furthermore, an alloy containing aluminum (an aluminum alloy)such as an alloy of aluminum and titanium, an alloy of aluminum andnickel, or an alloy of aluminum and neodymium; or an alloy containingsilver such as an alloy of silver and copper, an alloy of silver,copper, and palladium, or an alloy of silver and magnesium can be usedfor the conductive film. An alloy of silver and copper is preferablebecause of its high heat resistance. Moreover, a metal film or a metaloxide film is stacked on an aluminum alloy film, whereby oxidation ofthe aluminum alloy film can be suppressed. Examples of a material forthe metal film or the metal oxide film are titanium and titanium oxide.Alternatively, the conductive film having a property of transmittingvisible light and a film containing any of the above metal materials maybe stacked. For example, a stacked film of silver and ITO or a stackedfilm of an alloy of silver and magnesium and ITO can be used.

The electrodes may be formed separately by an evaporation method or asputtering method. Alternatively, a discharging method such as anink-jet method, a printing method such as a screen printing method, or aplating method may be used.

When a voltage higher than the threshold voltage of the light-emittingelement is applied between the lower electrode 831 and the upperelectrode 835, holes are injected to the EL layer 833 from the anodeside and electrons are injected to the EL layer 833 from the cathodeside. The injected electrons and holes are recombined in the EL layer833 and a light-emitting substance contained in the EL layer 833 emitslight.

The EL layer 833 includes at least a light-emitting layer. In additionto the light-emitting layer, the EL layer 833 may further include one ormore layers containing any of a substance with a high hole-injectionproperty, a substance with a high hole-transport property, ahole-blocking material, a substance with a high electron-transportproperty, a substance with a high electron-injection property, asubstance with a bipolar property (a substance with a high electron- andhole-transport property), and the like.

For the EL layer 833, either a low molecular compound or a highmolecular compound can be used, and an inorganic compound may also beused. Each of the layers included in the EL layer 833 can be formed byany of the following methods: an evaporation method (including a vacuumevaporation method), a transfer method, a printing method, an ink jetmethod, a coating method, and the like.

The light-emitting element is preferably provided between a pair ofinsulating films with low water permeability. Thus, an impurity such aswater can be prevented from entering the light-emitting element, leadingto prevention of a decrease in the reliability of the light-emittingdevice.

As an insulating film with low water permeability, a film containingnitrogen and silicon such as a silicon nitride film or a silicon nitrideoxide film, a film containing nitrogen and aluminum such as an aluminumnitride film, or the like can be used. Alternatively, a silicon oxidefilm, a silicon oxynitride film, an aluminum oxide film, or the like canbe used.

For example, the water vapor transmittance of the insulating film withlow water permeability is lower than or equal to 1×10′ [g/m²·day],preferably lower than or equal to 1×10⁻⁶ [g/m²·day], further preferablylower than or equal to 1×10⁻⁷ [g/m²·day], still further preferably lowerthan or equal to 1×10³¹ ⁸ [g/m²·day].

The insulating layers 813 and 843 are each preferably formed using aninsulating film with low water permeability.

As the insulating layer 815, for example, an inorganic insulating filmsuch as a silicon oxide film, a silicon oxynitride film, or an aluminumoxide film can be used. For example, as each of the insulating layers817, 817 a, and 817 b, an organic material such as polyimide, acrylic,polyamide, polyimide amide, or a benzocyclobutene-based resin can beused. Alternatively, a low-dielectric constant material (a low-kmaterial) or the like can be used. Furthermore, each of the insulatinglayers may be formed by stacking a plurality of insulating films.

The insulating layer 821 is formed using an organic insulating materialor an inorganic insulating material. As the resin, for example, apolyimide resin, a polyamide resin, an acrylic resin, a siloxane resin,an epoxy resin, or a phenol resin can be used. It is particularlypreferable that the insulating layer 821 be formed using aphotosensitive resin material so that a sidewall of an opening has aninclined surface with continuous curvature.

There is no particular limitation on the method for forming theinsulating layer 821; a photolithography method, a sputtering method, anevaporation method, a droplet discharging method (e.g., an ink jetmethod), a printing method (e.g., a screen printing method or an off-setprinting method), or the like may be used.

The spacer 827 can be formed using an inorganic insulating material, anorganic insulating material, a metal material, or the like. As theinorganic insulating material and the organic insulating material, forexample, a variety of materials that can be used for the insulatinglayer can be used. As the metal material, titanium, aluminum, or thelike can be used. When the spacer 827 containing a conductive materialand the upper electrode 835 are electrically connected to each other, apotential drop due to the resistance of the upper electrode 835 can besuppressed. The spacer 827 may have either a tapered shape or an inversetapered shape.

A conductive layer included in the light-emitting panel, which functionsas an electrode or a wiring of the transistor, an auxiliary electrode ofthe light-emitting element, or the like, can be formed to have asingle-layer structure or a stacked-layer structure using any of metalmaterials such as molybdenum, titanium, chromium, tantalum, tungsten,aluminum, copper, neodymium, and scandium, and an alloy materialcontaining any of these elements, for example. Alternatively, theconductive layer may be formed using a conductive metal oxide. As theconductive metal oxide, indium oxide (e.g., In₂O₃), tin oxide (e.g.,SnO₂), zinc oxide (ZnO), ITO, indium zinc oxide (e.g., In₂O₃—ZnO), orany of these metal oxide materials in which silicon oxide is containedcan be used.

The coloring layer is a colored layer that transmits light in a specificwavelength range. For example, a red (R) color filter for transmittinglight in a red wavelength range, a green (G) color filter fortransmitting light in a green wavelength range, a blue (B) color filterfor transmitting light in a blue wavelength range, or the like can beused. Each coloring layer is formed in a desired position with any ofvarious materials by a printing method, an ink-jet method, an etchingmethod using a photolithography method, or the like.

The light-blocking layer is provided between the adjacent coloringlayers. The light-blocking layer blocks light emitted from an adjacentlight-emitting element to prevent color mixture between adjacentlight-emitting elements. Here, the coloring layer is provided such thatits end portion overlaps with the light-blocking layer, whereby lightleakage can be suppressed. As the light-blocking layer, a material thatcan block light from the light-emitting element can be used; forexample, a black matrix may be formed using a resin material containinga metal material, pigment, or dye. Note that it is preferable to providethe light-blocking layer in a region other than the light-emittingportion, such as a driver circuit portion, in which case undesiredleakage of guided light or the like can be suppressed.

Furthermore, an overcoat covering the coloring layer and thelight-blocking layer may be provided. With the overcoat, impurities andthe like contained in the coloring layer can be prevented from beingdiffused into the light-emitting element. The overcoat is formed with amaterial that transmits light emitted from the light-emitting element;for example, an inorganic insulating film such as a silicon nitride filmor a silicon oxide film, an organic insulating film such as an acrylicfilm or a polyimide film can be used, and a stacked-layer structure ofan organic insulating film and an inorganic insulating film may be used.

In the case where upper surfaces of the coloring layer and thelight-blocking layer are coated with a material of the sealing layer, amaterial that has high wettability with respect to the material of thesealing layer is preferably used as the material of the overcoat. Forexample, an oxide conductive film such as an ITO film or a metal filmsuch as an Ag film that is thin enough to transmit light is preferablyused as the overcoat.

For the connector, it is possible to use a paste-like or sheet-likematerial which is obtained by mixing metal particles into athermosetting resin and for which anisotropic electric conductivity isprovided by thermocompression bonding. As the metal particles, particlesin which two or more kinds of metals are layered, for example, nickelparticles coated with gold are preferably used.

<Example of Manufacturing Method>

Next, an example of a method for manufacturing a light-emitting panel isdescribed with reference to FIGS. 10A to 10C and FIGS. 11A to 11C. Here,the manufacturing method is described using the light-emitting panel ofSpecific Example 1 (FIG. 8C) as an example

First, a separation layer 203 is formed over a formation substrate 201,and the insulating layer 813 is formed over the separation layer 203.Next, the plurality of transistors, the conductive layer 857, theinsulating layer 815, the insulating layer 817, the plurality oflight-emitting elements, and the insulating layer 821 are formed overthe insulating layer 813. An opening is formed in the insulating layers821, 817, and 815 to expose the conductive layer 857 (FIG. 10A).

In addition, a separation layer 207 is formed over a formation substrate205, and the insulating layer 843 is formed over the separation layer207. Next, the light-blocking layer 847, the coloring layer 845, and theovercoat 849 are formed over the insulating layer 843 (FIG. 10B).

The formation substrate 201 and the formation substrate 205 each can bea glass substrate, a quartz substrate, a sapphire substrate, a ceramicsubstrate, a metal substrate, or the like.

For the glass substrate, for example, a glass material such asaluminosilicate glass, aluminoborosilicate glass, or barium borosilicateglass can be used. When the temperature of the heat treatment performedlater is high, a substrate having a strain point of 730° C. or higher ispreferably used as the glass substrate. Note that by containing a largeamount of barium oxide (BaO), a glass substrate which is heat-resistantand more practical can be obtained. Alternatively, crystallized glass orthe like may be used.

In the case where a glass substrate is used as the formation substrate,an insulating film such as a silicon oxide film, a silicon oxynitridefilm, a silicon nitride film, or a silicon nitride oxide film ispreferably formed between the formation substrate and the separationlayer, in which case contamination from the glass substrate can beprevented.

The separation layer 203 and the separation layer 207 each have asingle-layer structure or a stacked-layer structure containing anelement selected from tungsten, molybdenum, titanium, tantalum, niobium,nickel, cobalt, zirconium, zinc, ruthenium, rhodium, palladium, osmium,iridium, and silicon; an alloy material containing any of the elements;or a compound material containing any of the elements. A crystalstructure of a layer containing silicon may be amorphous, microcrystal,or polycrystal.

The separation layer can be formed by a sputtering method, a plasma CVDmethod, a coating method, a printing method, or the like. Note that acoating method includes a spin coating method, a droplet dischargingmethod, and a dispensing method.

In the case where the separation layer has a single-layer structure, atungsten layer, a molybdenum layer, or a layer containing a mixture oftungsten and molybdenum is preferably formed. Alternatively, a layercontaining an oxide or an oxynitride of tungsten, a layer containing anoxide or an oxynitride of molybdenum, or a layer containing an oxide oran oxynitride of a mixture of tungsten and molybdenum may be formed.Note that a mixture of tungsten and molybdenum is an alloy of tungstenand molybdenum, for example.

In the case where the separation layer is formed to have a stacked-layerstructure including a layer containing tungsten and a layer containingan oxide of tungsten, the layer containing an oxide of tungsten may beformed as follows: the layer containing tungsten is formed first and aninsulating film formed of an oxide is formed thereover, so that thelayer containing an oxide of tungsten is formed at the interface betweenthe tungsten layer and the insulating film. Alternatively, the layercontaining an oxide of tungsten may be formed by performing thermaloxidation treatment, oxygen plasma treatment, nitrous oxide (N₂O) plasmatreatment, treatment with a highly oxidizing solution such as ozonewater, or the like on the surface of the layer containing tungsten.Plasma treatment or heat treatment may be performed in an atmosphere ofoxygen, nitrogen, or nitrous oxide alone, or a mixed gas of any of thesegasses and another gas. Surface condition of the separation layer ischanged by the plasma treatment or heat treatment, whereby adhesionbetween the separation layer and the insulating film formed later can becontrolled.

Each of the insulating layers can be formed by a sputtering method, aplasma CVD method, a coating method, a printing method, or the like. Forexample, the insulating layer is formed at a temperature higher than orequal to 250° C. and lower than or equal to 400° C. by a plasma CVDmethod, whereby the insulating layer can be a dense film with very lowwater permeability.

Then, a material for the sealing layer 823 is applied to a surface ofthe formation substrate 205 over which the coloring layer 845 and thelike are formed or a surface of the formation substrate 201 over whichthe light-emitting element 830 and the like are formed, and theformation substrate 201 and the formation substrate 205 are attached sothat these two surfaces face each other with the sealing layer 823provided therebetween (FIG. 10C).

Next, the formation substrate 201 is separated, and the exposedinsulating layer 813 and the substrate 801 are attached to each otherwith the adhesive layer 811. Furthermore, the formation substrate 205 isseparated, and the exposed insulating layer 843 and the substrate 803are attached to each other with the adhesive layer 841. Although thesubstrate 803 does not overlap with the conductive layer 857 in FIG.11A, the substrate 803 may overlap with the conductive layer 857.

Any of a variety of methods can be used as appropriate for theseparation process. For example, when a layer including a metal oxidefilm is formed as the separation layer on the side in contact with thelayer to be separated, the metal oxide film is embrittled bycrystallization, whereby the layer to be separated can be separated fromthe formation substrate. Alternatively, when an amorphous silicon filmcontaining hydrogen is formed as the separation layer between aformation substrate having high heat resistance and a layer to beseparated, the amorphous silicon film is removed by laser irradiation oretching, whereby the layer to be separated can be separated from theformation substrate. Alternatively, after a layer including a metaloxide film is formed as the separation layer on the side in contact withthe layer to be separated, the metal oxide film is embrittled bycrystallization, and part of the separation layer is removed by etchingusing a solution or a fluoride gas such as NF₃, BrF₃, or ClF₃, wherebythe separation can be performed at the embrittled metal oxide film.Further alternatively, a method carried out as follows may be employed:a film containing nitrogen, oxygen, hydrogen, or the like (e.g., anamorphous silicon film containing hydrogen, an alloy film containinghydrogen, or an alloy film containing oxygen) is used as the separationlayer, and the separation layer is irradiated with laser to release thenitrogen, oxygen, or hydrogen contained in the separation layer as gas,thereby promoting separation between the layer to be separated and theformation substrate. Still further alternatively, it is possible to usea method in which the formation substrate provided with the layer to beseparated is removed mechanically or by etching using a solution or afluoride gas such as NF₃, BrF₃, or ClF₃, or the like. In this case, theseparation layer is not necessarily provided.

When a plurality of the above-described separation methods are combined,the separation process can be performed easily. In other words,separation can be performed with physical force (by a machine or thelike) after performing laser irradiation, etching on the separationlayer with a gas, a solution, or the like, or mechanical removal with asharp knife, scalpel or the like so that the separation layer and thelayer to be separated can be easily separated from each other.

Separation of the layer to be separated from the formation substrate maybe performed by soaking the interface between the separation layer andthe layer to be separated in a liquid. Furthermore, the separation maybe performed while a liquid such as water is being poured.

As another separation method, in the case where the separation layer isformed using tungsten, it is preferable that the separation be performedwhile etching the separation layer using a mixed solution of ammoniumwater and a hydrogen peroxide solution.

Note that the separation layer is not necessarily provided in the casewhere separation at an interface between the formation substrate and thelayer to be separated is possible. For example, glass is used as theformation substrate, an organic resin such as polyimide, polyester,polyolefin, polyamide, polycarbonate, or acrylic is formed in contactwith the glass, and an insulating film, a transistor, and the like areformed over the organic resin. In this case, heating the organic resinenables the separation at the interface between the formation substrateand the organic resin. Alternatively, separation at the interfacebetween a metal layer and the organic resin may be performed in thefollowing manner the metal layer is provided between the formationsubstrate and the organic resin and current is made to flow in the metallayer so that the metal layer is heated.

Lastly, an opening is formed in the insulating layer 843 and the sealinglayer 823 to expose the conductive layer 857 (FIG. 11B). In the casewhere the substrate 803 overlaps with the conductive layer 857, anopening is formed also in the substrate 803 and the adhesive layer 841so that the conductive layer 857 is exposed (FIG. 11C). There is noparticular limitation on the method for forming the opening. Forexample, a laser ablation method, an etching method, an ion beamsputtering method, or the like may be used. As another method, a cut maybe made in a film over the conductive layer 857 with a sharp knife orthe like and part of the film may be separated by physical force.

In the above-described manner, the light-emitting panel can bemanufactured.

At least part of this embodiment can be implemented as appropriate incombination with any of the other embodiments described in thisspecification.

Embodiment 3

In this embodiment, structure examples of a foldable touch panel that isapplicable to a display portion included in the electronic device of oneembodiment of the present invention will be described with reference toFIGS. 12A to 12C, FIGS. 13A and 13B, FIGS. 14A to 14C, and FIGS. 15A to15C. Note that for a material of each layer, refer to Embodiment 2.

Structure Example 1

FIG. 12A is a top view of the touch panel. FIG. 12B is a cross-sectionalview taken along dashed-dotted line A-B and dashed-dotted line C-D inFIG. 12A. FIG. 12C is a cross-sectional view taken along dashed-dottedline E-F in FIG. 12A.

As illustrated in FIG. 12A, a touch panel 390 includes a display portion301.

The display portion 301 includes a plurality of pixels 302 and aplurality of imaging pixels 308. The imaging pixels 308 can sense atouch of a finger or the like on the display portion 301. Thus, a touchsensor can be formed using the imaging pixels 308.

Each of the pixels 302 includes a plurality of sub-pixels (e.g., asub-pixel 302R). In addition, in the sub-pixels, light-emitting elementsand pixel circuits that can supply electric power for driving thelight-emitting elements are provided.

The pixel circuits are electrically connected to wirings through whichselection signals are supplied and wirings through which image signalsare supplied.

Furthermore, the touch panel 390 is provided with a scan line drivercircuit 303 g(1) that can supply selection signals to the pixels 302 andan image signal line driver circuit 303 s(1) that can supply imagesignals to the pixels 302.

The imaging pixels 308 include photoelectric conversion elements andimaging pixel circuits that drive the photoelectric conversion elements.

The imaging pixel circuits are electrically connected to wirings throughwhich control signals are supplied and wirings through which powersupply potentials are supplied.

Examples of the control signals include a signal for selecting animaging pixel circuit from which a recorded imaging signal is read, asignal for initializing an imaging pixel circuit, and a signal fordetermining the time it takes for an imaging pixel circuit to detectlight.

The touch panel 390 is provided with an imaging pixel driver circuit 303g(2) that can supply control signals to the imaging pixels 308 and animaging signal line driver circuit 303 s(2) that reads out imagingsignals.

As illustrated in FIG. 12B, the touch panel 390 includes a substrate 510and a substrate 570 that faces the substrate 510.

Flexible materials can be favorably used for the substrate 510 and thesubstrate 570.

Materials with which passage of impurities is inhibited can be favorablyused for the substrate 510 and the substrate 570. For example, materialswith a vapor permeability of lower than or equal to 10⁻⁵ g/m²·day,preferably lower than or equal to 10⁻⁶ g/m²·day can be favorably used.

The substrate 510 can be favorably formed using a material whosecoefficient of linear expansion is substantially equal to that of thesubstrate 570. For example, the coefficient of linear expansion of thematerials are preferably lower than or equal to 1×10⁻³/K, furtherpreferably lower than or equal to 5×10⁻⁵/K, and still further preferablylower than or equal to 1×10⁻⁵/K.

The substrate 510 is a stacked body including a flexible substrate 510b, an insulating layer 510 a that prevents diffusion of impurities tothe light-emitting elements, and an adhesive layer 510 c that bonds theinsulating layer 510 a to the flexible substrate 510 b.

The substrate 570 is a stacked body including a flexible substrate 570b, an insulating layer 570 a that prevents diffusion of impurities tothe light-emitting elements, and an adhesive layer 570 c that bonds theinsulating layer 570 a to the flexible substrate 570 b.

For example, materials that include polyester, polyolefin, polyamide(e.g., nylon, aramid), polyimide, polycarbonate, or a resin having anacrylic bond, a urethane bond, an epoxy bond, or a siloxane bond can beused for the adhesive layer.

A sealing layer 360 bonds the substrate 570 to the substrate 510. Thesealing layer 360 has a refractive index higher than that of air. In thecase where light is extracted through the sealing layer 360, the sealinglayer 360 also serves as a layer (hereinafter, also referred to as anoptical bonding layer) that optically bonds two components (here, thesubstrates 510 and 570) between which the sealing layer 360 issandwiched. The pixel circuits and the light-emitting elements (e.g., afirst light-emitting element 350R) are provided between the substrate510 and the substrate 570.

Each of the pixels 302 includes the sub-pixel 302R, a sub-pixel 302G,and a sub-pixel 302B (FIG. 12C). The sub-pixel 302R includes alight-emitting module 380R, the sub-pixel 302G includes a light-emittingmodule 380G, and the sub-pixel 302B includes a light-emitting module380B.

For example, the sub-pixel 302R includes the first light-emittingelement 350R and the pixel circuit that can supply electric power to thefirst light-emitting element 350R and includes a transistor 302 t (FIG.12B). Furthermore, the light-emitting module 380R includes the firstlight-emitting element 350R and an optical element (e.g., a firstcoloring layer 367R).

The first light-emitting element 350R includes a first lower electrode351R, an upper electrode 352, and an EL layer 353 between the firstlower electrode 351R and the upper electrode 352 (FIG. 12C).

The EL layer 353 includes a first EL layer 353 a, a second EL layer 353b, and an intermediate layer 354 between the first EL layer 353 a andthe second EL layer 353 b.

The light-emitting module 380R includes the first coloring layer 367R onthe substrate 570. The coloring layer transmits light of a particularwavelength and is, for example, a layer that selectively transmits lightof red, green, or blue color. Note that a region that transmits lightemitted from the light-emitting element as it is may be provided aswell.

The light-emitting module 380R, for example, includes the sealing layer360 that is in contact with the first light-emitting element 350R andthe first coloring layer 367R.

The first coloring layer 367R is positioned in a region overlapping withthe first light-emitting element 350R. Accordingly, part of lightemitted from the first light-emitting element 350R passes through thesealing layer 360 that also serves as an optical bonding layer andthrough the first coloring layer 367R and is emitted to the outside ofthe light-emitting module 380R as indicated by arrows in FIGS. 12B and12C.

The touch panel 390 includes a light-blocking layer 367BM on thesubstrate 570. The light-blocking layer 367BM is provided so as tosurround the coloring layer (e.g., the first coloring layer 367R).

The touch panel 390 includes an anti-reflective layer 367 p positionedin a region overlapping with the display portion 301. As theanti-reflective layer 367 p, a circular polarizing plate can be used,for example.

The touch panel 390 includes an insulating layer 321. The insulatinglayer 321 covers the transistor 302 t. Note that the insulating layer321 can be used as a layer for planarizing unevenness caused by thepixel circuits. An insulating film on which a layer that can preventdiffusion of impurities to the transistor 302 t and the like is stackedcan be used as the insulating layer 321.

The touch panel 390 includes the light-emitting elements (e.g., thefirst light-emitting element 350R) over the insulating layer 321.

The touch panel 390 includes, over the insulating layer 321, a partition328 that overlaps with an end portion of the first lower electrode 351R.In addition, a spacer 329 that controls the distance between thesubstrate 510 and the substrate 570 is provided on the partition 328.

The image signal line driver circuit 303 s(1) includes a transistor 303t and a capacitor 303 c. Note that the driver circuit and the pixelcircuits can be formed in the same process over the same substrate. Asillustrated in FIG. 12B, the transistor 303 t may include a second gate304 over the insulating layer 321. The second gate 304 may beelectrically connected to a gate of the transistor 303 t. Alternatively,different potentials may be supplied to the second gate 304 and the gateof the transistor 303 t. The second gate 304 may be provided in atransistor 308 t, the transistor 302 t, or the like if necessary.

The imaging pixels 308 each include a photoelectric conversion element308 p and an imaging pixel circuit for sensing light received by thephotoelectric conversion element 308 p. The imaging pixel circuitincludes the transistor 308 t.

For example, a PIN photodiode can be used as the photoelectricconversion element 308 p.

The touch panel 390 includes a wiring 311 through which a signal can besupplied. The wiring 311 is provided with a terminal 319. Note that anFPC 309(1) through which a signal such as an image signal or asynchronization signal can be supplied is electrically connected to theterminal 319. Note that a printed wiring board (PWB) may be attached tothe FPC 309(1).

Transistors formed in the same process can be used as the transistor 302t, the transistor 303 t, the transistor 308 t, and the like. Embodiment2 can be referred to for the structures of the transistors.

As a gate, source, and drain of a transistor, and a wiring or anelectrode included in a touch panel, a single-layer structure or astacked-layer structure using any of metals such as aluminum, titanium,chromium, nickel, copper, yttrium, zirconium, molybdenum, silver,tantalum, and tungsten, or an alloy containing any of these metals asits main component can be used. For example, a single-layer structure ofan aluminum film containing silicon, a two-layer structure in which analuminum film is stacked over a titanium film, a two-layer structure inwhich an aluminum film is stacked over a tungsten film, a two-layerstructure in which a copper film is stacked over acopper-magnesium-aluminum alloy film, a two-layer structure in which acopper film is stacked over a titanium film, a two-layer structure inwhich a copper film is stacked over a tungsten film, a three-layerstructure in which a titanium film or a titanium nitride film, analuminum film or a copper film, and a titanium film or a titaniumnitride film are stacked in this order, a three-layer structure in whicha molybdenum film or a molybdenum nitride film, an aluminum film or acopper film, and a molybdenum film or a molybdenum nitride film arestacked in this order, and the like can be given. Note that atransparent conductive material containing indium oxide, tin oxide, orzinc oxide may be used. Copper containing manganese is preferably usedbecause controllability of a shape by etching is increased.

Structure Example 2

FIGS. 13A and 13B are perspective views of a touch panel 505. Forsimplicity, only main components are illustrated. FIGS. 14A to 14C arecross-sectional views along dashed-dotted line X1-X2 in FIG. 13A.

The touch panel 505 includes a display portion 501 and a touch sensor595 (FIG. 13B). Furthermore, the touch panel 505 includes the substrate510, the substrate 570, and a substrate 590. Note that the substrate510, the substrate 570, and the substrate 590 each have flexibility.

The display portion 501 includes the substrate 510, a plurality ofpixels over the substrate 510, and a plurality of wirings 511 throughwhich signals are supplied to the pixels. The plurality of wirings 511are led to a peripheral portion of the substrate 510, and part of theplurality of wirings 511 form a terminal 519. The terminal 519 iselectrically connected to an FPC 509(1).

The substrate 590 includes the touch sensor 595 and a plurality ofwirings 598 electrically connected to the touch sensor 595. Theplurality of wirings 598 are led to a peripheral portion of thesubstrate 590, and part of the plurality of wirings 598 form a terminal.The terminal is electrically connected to an FPC 509(2). Note that inFIG. 13B, electrodes, wirings, and the like of the touch sensor 595provided on the back side of the substrate 590 (on the substrate 510side) are indicated by solid lines for clarity.

As the touch sensor 595, a capacitive touch sensor can be used. Examplesof the capacitive touch sensor are a surface capacitive touch sensor anda projected capacitive touch sensor.

Examples of the projected capacitive touch sensor are a self capacitivetouch sensor and a mutual capacitive touch sensor, which differ mainlyin the driving method. The use of a mutual capacitive touch sensor ispreferable because multiple points can be sensed simultaneously.

An example of using a projected capacitive touch sensor will bedescribed below with reference to FIG. 13B.

Note that a variety of sensors that can sense the closeness or thecontact of a sensing target such as a finger can be used.

The projected capacitive touch sensor 595 includes electrodes 591 andelectrodes 592. The electrodes 591 are electrically connected to any ofthe plurality of wirings 598, and the electrodes 592 are electricallyconnected to any of the other wirings 598.

The electrodes 592 each have a shape of a plurality of quadranglesarranged in one direction with one corner of a quadrangle connected toone corner of another quadrangle as illustrated in FIGS. 13A and 13B.

The electrodes 591 each have a quadrangular shape and are arranged in adirection intersecting with the direction in which the electrodes 592extend.

A wiring 594 electrically connects two electrodes 591 between which oneelectrode 592 is positioned. The intersecting area of the electrode 592and the wiring 594 is preferably as small as possible. Such a structureallows a reduction in the area of a region where the electrodes are notprovided, reducing unevenness in transmittance. As a result, unevennessin luminance of light from the touch sensor 595 can be reduced.

Note that the shapes of the electrodes 591 and the electrodes 592 arenot limited to the above-mentioned shapes and can be any of a variety ofshapes. For example, the plurality of electrodes 591 may be provided sothat space between the electrodes 591 are reduced as much as possible,and a plurality of electrodes 592 may be provided with an insulatinglayer sandwiched between the electrodes 591 and the electrodes 592 andmay be spaced apart from each other to form a region not overlappingwith the electrodes 591. In that case, between two adjacent electrodes592, a dummy electrode that is electrically insulated from theseelectrodes is preferably provided, whereby the area of a region having adifferent transmittance can be reduced.

The touch sensor 595 includes the substrate 590, the electrodes 591 andthe electrodes 592 provided in a staggered arrangement on the substrate590, an insulating layer 593 covering the electrodes 591 and theelectrodes 592, and the wiring 594 that electrically connects theadjacent electrodes 591 to each other.

An adhesive layer 597 bonds the substrate 590 to the substrate 570 sothat the touch sensor 595 overlaps with the display portion 501.

The electrodes 591 and the electrodes 592 are formed using alight-transmitting conductive material. As the light-transmittingconductive material, a conductive oxide such as indium oxide, indium tinoxide, indium zinc oxide, zinc oxide, or zinc oxide to which gallium isadded can be used. Note that a film including graphene may be used aswell. The film containing graphene can be formed, for example, byreducing a film containing graphene oxide. As a reducing method, amethod with application of heat or the like can be employed.

The electrodes 591 and the electrodes 592 may be formed by depositing alight-transmitting conductive material on the substrate 590 by asputtering method and then removing an unnecessary portion by any ofvarious patterning techniques such as photolithography.

Examples of a material for the insulating layer 593 are a resin such asacrylic or epoxy resin, a resin having a siloxane bond, and an inorganicinsulating material such as silicon oxide, silicon oxynitride, oraluminum oxide.

Furthermore, openings reaching the electrodes 591 are formed in theinsulating layer 593, and the wiring 594 electrically connects theadjacent electrodes 591. A light-transmitting conductive material can befavorably used as the wiring 594 because the aperture ratio of the touchpanel can be increased. Moreover, a material with higher conductivitythan the conductivities of the electrodes 591 and the electrodes 592 canbe favorably used for the wiring 594 because electric resistance can bereduced.

One of the electrodes 592 extends in one direction, and a plurality ofelectrodes 592 are provided in the form of stripes.

The wiring 594 intersects with the electrodes 592.

Adjacent electrodes 591 are provided with one of the electrodes 592provided therebetween. The wiring 594 electrically connects the adjacentelectrodes 591.

Note that the plurality of electrodes 591 is not necessarily arranged inthe direction orthogonal to one electrode 592 and may be arranged tointersect with one electrode 592 at an angle of less than 90°.

One wiring 598 is electrically connected to any of the electrodes 591and the electrodes 592. Part of the wiring 598 serves as a terminal. Forthe wiring 598, a metal material such as aluminum, gold, platinum,silver, nickel, titanium, tungsten, chromium, molybdenum, iron, cobalt,copper, or palladium or an alloy material containing any of these metalmaterials can be used.

Note that an insulating layer that covers the insulating layer 593 andthe wiring 594 may be provided to protect the touch sensor 595.

Furthermore, a connection layer 599 electrically connects the wiring 598to the FPC 509(2).

As the connection layer 599, any of various anisotropic conductive films(ACF), anisotropic conductive pastes (ACP), and the like can be used.

The adhesive layer 597 has a light-transmitting property. For example, athermosetting resin or an ultraviolet curable resin can be used;specifically, a resin such as an acrylic resin, a urethane resin, anepoxy resin, or a resin having a siloxane bond can be used.

The display portion 501 includes a plurality of pixels arranged in amatrix. Each of the pixels includes a display element and a pixelcircuit for driving the display element.

In this embodiment, an example of using an organic EL element that emitswhite light as a display element will be described; however, the displayelement is not limited to such element.

For example, organic EL elements that emit light of different colors maybe included in sub-pixels so that the light of different colors can beemitted from the respective sub-pixels.

The substrate 510, the substrate 570, and a sealing layer 560 can havestructures similar to those in Structure Example 1.

A pixel includes a sub-pixel 502R, and the sub-pixel 502R includes alight-emitting module 580R.

The sub-pixel 502R includes a first light-emitting element 550R and apixel circuit including a transistor 502 t that can supply electricpower to the first light-emitting element 550R. Furthermore, thelight-emitting module 580R includes the first light-emitting element550R and an optical element (e.g., a coloring layer 567R).

The first light-emitting element 550R includes a lower electrode, anupper electrode, and an EL layer between the lower electrode and theupper electrode.

The light-emitting module 580R includes the first coloring layer 567R onthe light extraction side.

In the case where the sealing layer 560 is provided on the lightextraction side, the sealing layer 560 is in contact with the firstlight-emitting element 550R and the first coloring layer 567R.

The first coloring layer 567R is positioned in a region overlapping withthe first light-emitting element 550R. Accordingly, part of lightemitted from the first light-emitting element 550R passes through thefirst coloring layer 567R and is emitted to the outside of thelight-emitting module 580R as indicated by an arrow in FIG. 14A.

The display portion 501 includes a light-blocking layer 567BM on thelight extraction side. The light-blocking layer 567BM is provided so asto surround the coloring layer (e.g., the first coloring layer 567R).

The display portion 501 includes an anti-reflective layer 567 ppositioned in a region overlapping with pixels. As the anti-reflectivelayer 567 p, a circular polarizing plate can be used, for example.

The display portion 501 includes an insulating film 521. The insulatingfilm 521 covers the transistor 502 t. Note that the insulating film 521can be used as a layer for planarizing unevenness caused by the pixelcircuits. A stacked film including a layer that can prevent diffusion ofimpurities can be used as the insulating film 521. This can prevent thereliability of the transistor 502 t or the like from being lowered bydiffusion of impurities.

The display portion 501 includes the light-emitting elements (e.g., thefirst light-emitting element 550R) over the insulating film 521.

The display portion 501 includes, over the insulating film 521, apartition 528 that overlaps with an end portion of a first lowerelectrode. In addition, a spacer that controls the distance between thesubstrate 510 and the substrate 570 is provided on the partition 528.

A scan line driver circuit 503 g(1) includes a transistor 503 t and acapacitor 503 c. Note that the driver circuit and the pixel circuits canbe formed in the same process over the same substrate.

The display portion 501 includes the wirings 511 through which signalscan be supplied. The wirings 511 are provided with the terminal 519.Note that the FPC 509(1) through which a signal such as an image signalor a synchronization signal can be supplied is electrically connected tothe terminal 519.

Note that a printed wiring board (PWB) may be attached to the FPC509(1).

The display portion 501 includes wirings such as scan lines, signallines, and power supply lines. Any of various conductive films describedthe above can be used as the wirings.

Note that any of various kinds of transistors can be used in the displayportion 501. A structure in the case of using bottom-gate transistors inthe display portion 501 is illustrated in FIGS. 14A and 14B.

For example, a semiconductor layer containing an oxide semiconductor,amorphous silicon, or the like can be used in the transistor 502 t andthe transistor 503 t illustrated in FIG. 14A.

For example, a semiconductor layer containing polycrystalline siliconthat is obtained by crystallization process such as laser annealing canbe used in the transistor 502 t and the transistor 503 t illustrated inFIG. 14B.

A structure in the case of using top-gate transistors in the displayportion 501 is illustrated in FIG. 14C.

For example, a semiconductor layer including polycrystalline silicon, asingle crystal silicon film that is transferred from a single crystalsilicon substrate, or the like can be used in the transistor 502 t andthe transistor 503 t illustrated in FIG. 14C.

Structure Example 3

FIGS. 15A to 15C are cross-sectional views of a touch panel 505B. Thetouch panel 505B described in this embodiment is different from thetouch panel 505 described in Structure Example 2 in that the displayportion 501 displays received image data to the side where thetransistors are provided and that the touch sensor is provided on thesubstrate 510 side of the display portion. Different structures will bedescribed in detail below, and the above description is referred to forthe other similar structures.

The first coloring layer 567R is positioned in a region overlapping withthe first light-emitting element 550R. The first light-emitting element550R illustrated in FIG. 15A emits light to the side where thetransistor 502 t is provided. Accordingly, part of light emitted fromthe first light-emitting element 550R passes through the first coloringlayer 567R and is emitted to the outside of the light-emitting module580R as indicated by an arrow in FIG. 15A.

The display portion 501 includes the light-blocking layer 567BM on thelight extraction side. The light-blocking layer 567BM is provided so asto surround the coloring layer (e.g., the first coloring layer 567R).

The touch sensor 595 is provided on the substrate 510 side of thedisplay portion 501 (FIG. 15A).

The adhesive layer 597 is provided between the substrates 510 and 590and bonds the touch sensor 595 to the display portion 501.

Note that any of various kinds of transistors can be used in the displayportion 501. A structure in the case of using bottom-gate transistors inthe display portion 501 is illustrated in FIGS. 15A and 15B.

For example, a semiconductor layer containing an oxide semiconductor,amorphous silicon, or the like can be used in the transistor 502 t andthe transistor 503 t illustrated in FIG. 15A.

For example, a semiconductor layer containing polycrystalline silicon orthe like can be used in the transistor 502 t and the transistor 503 tillustrated in FIG. 15B.

A structure in the case of using top-gate transistors in the displayportion 501 is illustrated in FIG. 15C.

For example, a semiconductor layer containing polycrystalline silicon, atransferred single crystal silicon film, or the like can be used in thetransistor 502 t and the transistor 503 t illustrated in FIG. 15C.

At least part of this embodiment can be implemented as appropriate incombination with any of the other embodiments described in thisspecification.

This application is based on Japanese Patent Application serial no.2014-024647 filed with Japan Patent Office on Feb. 12, 2014, the entirecontents of which are hereby incorporated by reference.

What is claimed is:
 1. An electronic device comprising: a camera; and aflexible display, wherein the flexible display comprises a first regionand a second region, wherein the first region surrounds the camera,wherein the first region is configured to emit white light to illuminatea photographic subject while the camera is shooting an image of thephotographic subject, and wherein the second region is configured todisplay the image shot by the camera.
 2. The electronic device accordingto claim 1, wherein the first region emits light in a first direction,wherein the second region emits light in a second direction, and whereinthe first direction is different from the second direction.
 3. Theelectronic device according to claim 1, wherein the flexible display isconfigured to freely change a size of the first region by a user.
 4. Theelectronic device according to claim 1, wherein the entirety of thefirst region emits white light.
 5. The electronic device according toclaim 1, wherein a part of the first region emits white light.
 6. Anelectronic device comprising: a camera; and a flexible display, whereinthe flexible display comprises a first region and a second region,wherein the first region surrounds the camera, wherein the first regionemits white light to illuminate a photographic subject while the camerais shooting an image of the photographic subject, and wherein theflexible display is configured to change a size of a flexible displayportion emitting white light to the photographic subject.
 7. Theelectronic device according to claim 6, wherein the second region isconfigured to display an image shot by the camera while the first regionemits white light to the photographic subject.
 8. The electronic deviceaccording to claim 6, wherein the first region emits light in a firstdirection, wherein the second region emits light in a second direction,and wherein the first direction is different from the second direction.9. The electronic device according to claim 6, wherein the entirety ofthe first region emits white light.
 10. The electronic device accordingto claim 6, wherein a part of the first region emits white light. 11.The electronic device according to claim 1, wherein a light emitted in ashooting direction by the electronic device comprises a single color.12. The electronic device according to claim 6, wherein a light emittedin a shooting direction by the electronic device comprises a singlecolor.